Fuel supply system



Oct. 24, 1961 G. M. HOLLEY, JR

FUEL SUPPLY SYSTEM 4 Sheets-Sheet 1 Filed Nov. 22, 1957 INVENTOR.

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FUEL SUPPLY SYSTEM 4 Sheets-Sheet 2 Filed Nov. 22, 1957 INVEN TOR. 650265/14/70L4fY/.

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FUEL SUPPLY SYSTEM 4 Sheets-Sheet 4 Filed Nov. 22, 1957 NMN NMN

a. mi 3% l mmm SwN mmw mmw United States Patent 3,005,625 FUEL SUPPLY SYSTEM George M. Holley, Jr., Grosse Pointe Park, Mich., as-

signor to Holley Carburetor Company, Van Dyke, Mich, a corporation of Michigan Filed Nov. 22, 1957, Ser. No. 698,221 9 Claims. (Cl. 261-23) This invention relates to pressure regulated fuel systems for internal combustion engines, andmore particularly to such fuel systems which have a secondary fuel injection system.

Fuel injection systems having separate nozzles for the individual cylinders are believed to be desirable at higher speeds and at times when greater fuel flow is necessary. However, such multiple nozzle systems have the problem of properly metering the fuel at low fuel flow, such as at idle or at very low engine speeds.

Accordingly, an object of this invention is to provide a secondary fuel supply means which will insure a proper supply of fuel to each engine cylinder.

Another object of the invention is to provide a combination of fuel systems which will provide an eflicient means of fuel distribution to the cylinders during times of low fuel flow.

Still another object of the invention is to provide means to automatically select the particular fuel system or combination of fuel systems in order to satisfy engine requirements.

Other features, objects and advantages of the invention will become apparent when reference is made to the following specification and drawings in which:

FIGURE 1 is a diagrammatic view illustrating one embodiment of the invention;

FIGURE 2 is a plan view illustrating the invention shown in FIGURE 1;

FIGURE 3 is a diagrammatic view illustrating another embodiment of the invention;

FIGURE 4 is a diagrammatic view illustrating still another embodiment of the invention.

Referring to FIGURE 1 in greater detail, a throttle body It) is provided with a throttle valve 11 mounted on the throttle shaft 12 and adapted to control the flow of motive fluid through the intake passage 13. A conduit for metered fuel at 14 may be made as an integral part of the throttle body 10. A port 15 adapted to be controlled by needle valve 18 communicates with conduit 14 and the induction passage 13.

A flow valve 16, comprised of body 17, needle valve 18, an inner cavity 23, and -a threaded portion 19, is secured by any suitable means to the throttle body in such a way as to have the valves 18 in direct alignment with port 15. A spring 22 mounted about the shank of the needle valve between the valve body 17 and the needle head 21 is used to apply pressure against the threads 19 so as to insure against accidental movement of said needle valve by either vibration or any other cause. A conduit 24 communicates between the cavity 23 of valve 16 and fuel manifold 25 and is adapted to be controlled by a solenoid actuated valve indicated generally at 20. The manifold 25 supplies fuel, by means of individual conduits 28 to nozzles 26 which are appropriately positioned in the intake manifold 27 so as to inject fuel into the intake manifold in close proximity to the respective intakes of the engine cylinders.

A suction responsive switch 29 is substantially comprised of a diaphragm 3t securely held between the throttle body 10, thereby forming a chamber 31 formed within said body, and housing 32. Electrical contacts 33 and 34 having terminals 35 and 36 are placed within the housing 32. A rod 37 having an electrical conductor 38 secured to its one end is secured to and adapted to move with the Patented Oct. 24, 1961 diaphragm 30. A spring 39 mounted within chamber 31 normally biases diaphragm 3t) and rod 37 to the left. Chamber 40 formed by housing 32 and diaphragm 30 is vented to the atmosphere by means of port 41 while chamber 31 communicates with the induction passage 13, at a point posterior to the throttle valve by means of port 42.

An electrical switch 43 is mounted stationary with respect to the throttle body 10 and is adapted to be controlled by a suitable linkage opcratively connected to the throttle shaft 12 as shown in view A of FIGURE 1. The switch is substantially comprised of a housing 44 having a substantially cylindrical cavity 45 therein containing a suitable piston-like electrical conductor 46. Electrical contacts 47 and 48 are placed at one end of said housing so as to enable conductor 46 to contact both simultaneously when required. A shaft 49 made of a suitable non-conducting material is fixed to the conductor 46 at one end and is in contact with lever 50 at its other end. A spring 51 mounted within cavity 45 normally biases the shaft and conductor 46 upwardly. The lever 50 is pivoted at some point 52 and has one of its ends in contact with shaft 49 of switch 43 while the other end is in contact with the cam 53 which is mounted on the throttle shaft 12.

The solenoid actuated flow control valve 2%) is substantially comprised of a housing 54, having a chamber 55 formed therein containing a valve 56 connected to a shaft 57 whose position is controlled by solenoid 58.

Terminal 35 of switch 29 is electrically connected to terminal 59 of solenoid 58 while terminal 36 is electrically connected to terminal 60 of battery 61. Terminal 62 of the battery is then connected to terminal 63 of switch 43 while terminal 64 of said switch is connected to terminal 65 of the solenoid 58.

Operation of invention as shown in FIGURE 2 During engine cranking the throttle valve 11 is in a substantially closed position, switch 43 is open and the vacuum operated switch 29 is closed. The fuel coming from some metering source 66 (FIGURE 2) enters conduit 14 and passes through port 15 into the throttle intake passage 13. Although the invention as shown in FIG- URE 2 discloses a throttle body having a single throttle valve and a single induction passage it is of course obvious that a structure having multiple throttle valves and/or multiple induction passages would still be embraced in the scope of this invention. If such a structure having multiple induction passages was used, the fuel could still be delivered to a conduit 14 and then through a single metering valve such as 16, then through a port 15 from which it would flow through separate passages into the respective induction passages.

While the fuel is being dischargedthrough port 15, it also flows into chamber 23 and conduit 24. However, it is unable to flow past valve 20 because of its normally closed position.

When the engine starts, manifold vacuum is transmitted to chamber 31 causing a pressure differential across diaphragm 30 which is sufiicient to overcome the force of spring 39. and move the diaphragm and electrical con- (motor 38 to the right thereby opening the electrical circuit through switch 29.

Thus it can readily be seen that during engine cranking and during relatively low engine speeds, the incoming metered fuel passes only through conduit 14, port 15, sprays into the intake passage 13 and flows as a fuel air mixture into a conventional intake manifold supplying the engine cylinders. No fuel is delivered into the fuel manifold 25 because during this range of engine operation one or both of the electrical switches, controlling the position of solenoid 58 are open.

where the manifold vacuum is not sufiicient to overcome the force of spring 39; the electrical circuit through switch 29 will be closed by virtue of conductor 38 coming into contact with electrical contacts 33 and 34. At approximately this same instant the throttle valve 11 will have opened a sufficient degree so as to cause cam 53 to rotate lever 54) clockwise about pivot 52 thereby depressing shaft 49 so as to bring conductor '46 into contact with electrical contacts 47 and 48. At this instant the electrical circuit through switches 29 and 43, solenoid 58 and battery 61 will'be completed thereby energizing solenoid 58 and opening the valve 20. Fuel is then allowed to flow through conduit 24 into the fuel manifold 25 from where it is distributed to the individual cylinders by means of conduits 28 and nozzles 26.

Realizing that the position of the throttle valve and the manifold vacuum are the controlling factors in this particular disclosure, it becomes apparent that this invention has an additional desirable feature, that is, as an accelerating device. If the engine should be operating at some relatively low speed and the throttle valve was suddenly opened to some degree approaching wide open throttle position, the manifold vacuum would be sharply reduced. This reduction in manifold vacuum would cause switch 29 to close for some time thereby completing the electrical circuit controlling the solenoid valve 20. It becomes evident then that additional fuel would be delivered to the individual cylinders thereby giving smooth instantaneous acceleration.

It should be mentioned that any combination of devices such as fly-ball governors or any speed sensitive devices and/ or pressure responsive devices could. be used instead of the throttle linkages 53 and 53 and switch 29. It is not intended that this embodiment of the invention be limited to the exact devices illustrated.

Referring now to FIGURE 3, metered fuel enters at 111 and flows through conduit 11% and passes around the pressure valve 113 into the intake passage of a throttle body (not shown). A venturi 112, within conduit 110 has an annular opening 131 which is in communication with conduit 114 and chamber 116 formed by housing 128 and diaphragm 117, which is held securely between housings 128 and 127.

A contour valve 121 in chamber 119 is adapted to control the How of fuel through conduit 123 which is in communication with chamber 119, conduit 118 and conduit 11%. Valve 121 is normally held closed against its seat 124 by diaphragm 117 and spring 120. Spring 122 within chamber 119 normally tends to raise the valve 121 from its seat. However, its force is not sufiicient to overcome the force of spring 120. A check valve 124- is positioned in the lower part of conduit 123 and is held closed against its metering edges 125 by means of spring 126.

Conduit 123, when pressure valve 124 is open, is in communication with fuel manifold 129 which may be similar in all respects to manifold 25 of FIGURE 2. The manifold 129 also has individual conduits 130 leading to the individual engine cylinders in the same manner as conduits 28 of the invention illustrated in FIG- URE 1.

Operation of invention as shown in Figure 3 During engine cranking and times of relatively low engine speed, the metered fuel flows into conduit 1 filling chambers 116 and 119' through the respective conduits 114 and 118, and forces pressure valve 113 open by lifting it off of its metering edges 132against the force of spring 133. The fuel then passes around valve 113 and into the intake passage of a throttle body (not shown) where it is mixed with the incoming air. Throughout this range of relatively low engine speeds, spring 120 has sufiicient force to overcome any pressure differential which may exist between conduit 114 and conduit 118.

Therefore, the fuel continues to flow around valve 113 and into the throttle body in the conventional manner. However, when the engine attains some predetermined speed, the rate of fuel flow through conduit 110 will reach a value whereby a pressure diiferential will be created between conduits 114 and 118 which will be sufiicient to overcome the force of spring 120. In order that slight variations in fuel flow will not cause the diaphragm 117 to flutter, a restriction 115 is placed within conduit 114 as a damping means.

When the diaphragm 117 moves upwardly against spring 126, valve 121 is raised a corresponding amount by spring 122 and the fuel is then metered by valve 121 and its metering edges 134 in accordance with the amount that said valve is raised. The fuel then flows into conduit 123 and forces valve 124 off of its metering edges 125. As the fuel flows around valve 125 it passes into fuel manifold 129 from where it flows into the individual conduits 131 which in turn supply the individual engine cylinders in the same manner as conduits 28 of FIG- URE 2.

It is apparent that the selection of springs 126 and 133 is important in that the choice of spring rates in both will ultimately determine the type of fuel system. That is, once the valve 121 is opened the following conditions can exist, depending on the respective spring rates:

(1) If the rates of springs 133 and 123' are equal, fuel will be delivered into the engine intake manifold through both systems.

(2) If the rate of spring 133 is much greater than that of spring 123 then the valve 113 will close and all of the fuel will be delivered through the individual cylinders by means of conduits 130.

(3) If the rate of spring 133 is slightly greater then valve 113 will more nearly close, but fuel will still be delivered to a small degree through the throttle body and into the intake manifold, while'the greater amount of fuel will pass through the individual conduits 139.

It is understood that the modification. of FIGURE 3 is not limited to the exact device illustrated. Certain changes such as a speed sensitive device (a fly-ball governor, perhaps) could be used to regulate valve 121 instead of the pressure switch and diaphragm 117. An electrical circuit such as shown in FIGURE 2 could be employed to actuate a solenoid which would open valve 121, or even a venturi in the throttle body induction passage could be used to cooperate with some pressure responsive valve in order to open valve 121.

Referring to FIGURE 4, a pressure responsive valve 233 is in communication with a second pressure respon sive valve 219 by means of conduit 215 which constrains a fluid flow valve 216. Valve 233 is substantially comprised of housings 213 and 235'which form chambers 212 and 240 by virtue of the diaphragm 214 securely held between them. A conduit 246 communicates with chamber 212 and is adapted to be controlled by a valve member 234 which is secured to the diaphragm 214. Chamber 24% which is vented to the atmosphere by port 239 contains a spring 236 which normally biases the diaphragm 214 and valve member 234 downwardly.

Flow valve 216 being substantially circular in crosssection, contains ports 218. An arm 242 normally biased counter-clockwise by a spring 245 and spring abutment 244, controls the position of the valve 216- and conse quently the position of the ports 218. The arm 242 is operatively connected through a spring loaded lost-motion coupling 241 to the throttle linkage indicated generally at 243.

The pressure responsive valve 219 is generally comprised of housings 228 and 225 which form chambers 227 and 224 by virtue of the diaphragm 221 held securely between them. A conduit 229 is in communication with chamber 227 and fuel manifold chamber 230 (similar to 25 of FIGURES 1 and 2) and is adapted to be controlled by a valve member 220 which is secured to diaphragm 221. Chamber 224, vented to the atmosphere by port 226, contains a spring 222 which normally biases the diaphragm 221 and valve member 220 downwardly. The fuel manifold 231 has individual conduits 232 leading to nozzles 26 as shown in FIGURE 1.

Operation of invention as shown in FIGURE 4 During engine cranking the arm 242 would be in the position illustrated thereby closing ofi the flow of fuel to valve 219. Metered fuel entering conduit 210 at 211 fills cavity 212 and conduit 215, to the right of valve 216, and raises the valve member 234 off of its seat 238' by virtue of the pressure differential created across diaphragm 214. It can readily be seen that the amount of movement of member 234 is -a function of fuel pressure which in turn is dependent on engine speed. The fuel which is metered between member 234 and its seat 238 passes through conduit 246 and into the intake passage of the throttle body. The motive fluid will be supplied in this manner during relatively low engine speeds.

However, when the engine speed is increased or when the engine is placed under a relatively heavy load, the linkage 243 will turn arm 242 against the force of spring 245 thereby turning valve 216 in a clockwise direction so that ports 218 will be in at least partial registry with conduit 215. As soon as valve 216 starts to open, metered fuel passes through into chamber 220 of valve 219. The valve member 220 is raised from its seat 223 in the same manner as was member 234. The fuel which is metered between member 220 and its seat 223 passes through conduit 229 into the manifold chamber 230 and through the individual conduits 232 to the engine cylinders.

It should be noticed that if spring rate of 245 is higher than the spring rate within the lost motion coupling 241, the operator will have a definite feel of when he starts opening valve 216.

It is to be understood, of course, that the throttle body having an intake passage 13 communicating with the manifold 27 having individual fuel lines 28 with nozzles 26 discharging into the inlet manifold, as shown by FIGS. 1 and 2, are necessarily a part of the modifications of FIGS. 3 and 4 also.

While three modifications of the invention have been described for purposes of illustration, others will become evident to those skilled in the art without resorting to inventive process.

What I claim is:

1. In a pressure regulated fuel system for an internal combustion engine having an intake manifold with an induction passage therein, a throttle body having an intake passage communicating with said induction passage, a throttle valve controlling the flow of motive fluid through said intake passage, first means discharging fuel under a pressure above atmospheric within said intake passage at all times during engine operation, and second means including a fuel manifold for supplying fuel to said induction passage at a plurality of points downstream from the discharge of said first means.

2. In a pressure regulated fuel system for .internal combustion engines having a plurality of cylinders, a throttle body having an air induction passage therein, a throttle valve controlling the flow of said air through said induction passage, a conduit supplying all of the liquid fuel required by said engine, first means communicating with said conduit and responsive to the fuel pressure Within said conduit for supplying fuel at a single point within said induction passage, and a second means communicating at times with said conduit and responsive to the rate of fuel flow through said conduit for supplying fuel to said induction passage at points downstream of said previously mentioned single point and in relatively close proximity to said cylinders of said engine.

3. In a pressure regulated fuel system for internal combustion engines having a plurality of engine cylinders, a throttle body having an air induction passage therein, a throttle valve controlling the flow of said air through said induction passage, a conduit having a venturi therein for supplying all of the liquid fuel required by said engine, first means communicating with said conduit downstream of said venturi discharging fuel at a point within said induction passage and second means responsive to the fuel flow past said venturi for discharging fuel into said induction passage at points downstream of the point of discharge of said first means and in relatively close proximity to the individual cylinders of said engine.

4. In a pressure regulated fuel system for internal combustion engines, a throttle body having an air induction passage therein, a throttle valve controlling the flow of said air through said induction passage, an intake m-anifold communicating with said induction passage, a sepa rate conduit having a venturi therein supplying all of the liquid fuel required by said engine, first means communicating with said conduit supplying fuel at point within said induction passage, and second means in communication with the throat of said venturi and with said separate conduit supplying fuel at different points within said intake manifold.

5. In a pressure regulated fuel system for an internal combustion engine having a plurality of cylinders, a body having an air intake passage, a throttle valve controlling the flow of said air through said passage, a separate conduit for supplying liquid metered fuel, said fuel having a pressure in accordance with engine requirements, first means communicating between said separate conduit and said intake passage posterior to saidthrottle valve for supplying fuel to said passage during all engine operating conditions, and second means downstream to said first means for at times supplying additional fuel at different points within said intake passage downstream of where said first means supplies fuel to said intake passage.

6. A fuel injection system for an internal combustion engine having a plurality of cylinders, conprising a source of pressurized metered liquid fuel, an air induction passage an intake manifold communicating between said induction passage and said individual cylinders, a manually operable throttle valve for controlling only the flow of said air through said induction passage, a first separate conduit communicating between said source of pressurized metered liquid fuel and a discharge orifice within said induction passage posterior to said throttle valve, said discharge orifice and said first conduit functioning to supply liquid fuel under positive pressure to said induction .passage during all ranges of engine operation, a fuel manifold, individual nozzles for supplying fuel to said air induction passage at points in close proximity to said individual cylinders connected to said fuel manifold, a second conduit portion connected to said first conduit downstream of said discharge orifice and adapated to at times supply metered fuel under positive pressure to said fuel manifold and said nozzles, and electrically operated valve means connected Within said second conduit for initiating and terminating fuel flow through said second conduit in accordance with engine load and throttle valve position.

7. A fuel injection system for an internal combustion engine having a plurality of cylinders, comprising an air induction passage, a first conduit including a venturi therein for conveying pressurized metered liquid fuel to a single point of discharge within said induction passage, and pressure responsive valve means for conveying liquid fuel to said induction passage at different points downstream of said single point, said pressure responsive valve means comprising a housing divided generally into first and second chambers by a diaphragm member, a second conduit communicating between the throat of said venturi and said first chamber, a third conduit communicating between said second chamber and said first conduit at a point downstream of said venturi, a liquid fuel manifold,

a fourth conduit communicating between said second chamber and said fuel manifold, valve means positioned in accordance with the position of said diaphragm member for controlling the flow of liquid fuel through said fourth conduit to said fuel manifold, and a plurality of individual fuel conduits each communicating between said fuel a manifold and said induction passage at points in relatively close proximity to said cylinders.

8. A fuel system for an i ternal combustion engine having an induction passage with a throttle controlling the flow therethrough, comprising a first fuel system for supplying fuel to the induction passage posterior to said throttle 'valve, a second fuel system for supplying additional fuel to the individual cylinders of said engine, and automatic means responsive to fuel flow in said first fuel system for operating said second system, said automatic means comprising a venturi meter in said first fuel system for measuring the rate of fuel flow therethrough, and valve means controlled by said venturi meter for initiating fuel flow through said second fuel system when a predetermined rate of fuel flow through said first fuel system has been achieved.

9. A fuel injection system for an internal combustion engine having a plurality of cylinders, comprising a source of pressurized metered liquid fuel, an intake manifold leading to said cylinders, an induction passage communicating with said intake manifold, a throttle valve controlling the flow of air through said induction passage, a fuel discharge orifice communicating with said induction passage posterior to said throttle valve, a first conduit for conveying said liquid fuel from said source to said discharge orifice, a liquid fuel'manifold, individual fuel nozzles communicating between each of said cylinders and said fuel manifold, a. second conduit communicating between said first conduit and said fuel manifold, valve means for controlling the flow through said second conduit, and automatic means for actuating said valve means to either open said valve means and allow fuel flow through said second conduit or close said valve means and terminate fuel flow through said second conduit, said automatic means comprising a source of electrical energy, an electrical circuit including said source of electrical energy, a first electrical switch connected in said circuit and responsive to intake manifold vacuum adapted to open said circuit on occurrence of high manifold vacuum, a second electrical switch connected in said circuit and responsive to the position of said throttle valve adapted to close said electrical circuit when said throttle moves to a more nearly wide open position and electric motor means connected in said circuit and to said valve means for moving said valve means to an open position whenever said circuit is closed.

References Cited in the file of this patent UNITED STATES PATENTS 2,094,555 7 Von Hilvety Sept. 28, 1937 2,724,375 Schaffer Nov. 22, 1955 2,798,703 Carlson et a1. July 9, 1957 2,816,745 McCain Dec. 17, 1957 2,823,018 Glynn Feb. 11, 1958 FOREIGN FATENTS 466,164 Great Britain May 18, 1937 

